This is a multicenter, randomized double-blind, placebo controlled, parallel-group study designed to evaluate the efficacy of 0.1pg/kg rhNGF administered subcutaneously three times per week with subjects with diabetic neuropathy (symptomatic and asymptomatic) and asymptomatic Type I and Type II diabetes mellitus. The study will be conducted in about 1300 patients at up to 100 centers in the United States. There will be 16 scheduled visits over a 13 month period of time. The diabetes mellitus will be kept under control with whatever medication adjustments are necessary. Certain medications prescribed for treatment of the peripheral neuropathy may continue while others are excluded. One may choose not to participate if the medications you wish to take are not on the allowed list.